overboost issue solved rb25

[hungryjoseph]

I've had this problem for a while and figured I'd post this up as another reference.

I had an AM performance downpipe with the external dump. It would leak where the dump was and cause exhaust to go into the car when it was moving with the windows down. I also had issues with overboosting. I even left the wastegate all the way open with the actuator rod off and it still overboosted to 14+psi. Swapping over to the syko turbo elbow solve both of these problems. This literally solved all the significant problems I've had with the motor.

[Carl H]

odd that you would have overboosting problems with that piece, i've installed and used several and had zero issues.

[hungryjoseph]

Don't really know what to say other than I swapped it out and it doesn't overboost

[Darius]

Was the internal WG flap interfering with something on the interior of the AM Performance elbow causing it to not open fully? I could see the stub of tubing that extends past the turbo flange interfering with the flapper of the WG. It might just need a little shortening.

[hungryjoseph]

the WG flap doens't need to open a full 90 degrees for it to work. I dont know about your actuators but none of mine on any motor ever open the WG all the way. If anything the Syko elbow restricts the movement even more than the AM performance downpipe does because a flat plate is covering the WG area.

[daemonyk]

Apparently it has happened before am-performance-downpipe-issues-t258602.html pretty much same exact deal. Doesn't really help with a fix aside from "put other dump pipe back in", but it does at least show that it's something that can / does occur

[hungryjoseph]

I thought it might have been a problem with the turbo but that doesn't seem to be the case since this is the second turbo that the boost creep happened on.

[daemonyk]

Yeah, very few people seem to have that problem. But the fact that others do have it does lend some credibility to things. My best wild stab in the dark pulled out of my arse guess is that sometimes when the planets are aligned and the moon is in the 8th house of aquarius, a weird mutant dump pipe gets made where the laws of fluid dynamics are suspended and rogue backpressure can make the WG pull a reverse BOV and not open despite the urging of the actuator - and it may just take full-load exhaust gas pressure to make it happen Or something like that. The world may never know.